Expand Cell Styles Ribbon

All the sudden, the colors on the "cell styles" ribbon don't have the preview display, so I have to click it to open the dropdown, and then click the color I want. This has happened before, and I ultimately created a new tab with just cell styles, and that seemed to work, but it just went away all the sudden. I want it to the show the preview with a couple colors that I can click on without having to click cell styles and open the dropdown. Please advise. Thanks in advance.